As is well known, an optical fiber has many advantages over an electrical conductor, such as the optical fiber's wide bandwidth, its high immunity to electromagnetic radiation, and its ability to conduct signals with very low levels of signal loss. Because of these and other advantages of the optical fiber and of optical communication in general, optical fibers are rapidly replacing electrical conductors in many communication systems.
The application of optical fiber-to-the-home (FTTH), however, has been rather slow. An impediment to a FTTH architecture is the cost of the optical unit at the home. In particular, providing the customer with an optical link upstream in the network. Such a link would require connecting an optical fiber to an active optical device, such as a modulator or laser. The active optical device of a modulator or laser would be necessary in a home in order to provide the home with the capability of transmitting optical signals that have been encoded with information from the home.
Presently, the coupling of an optical fiber to an active optical device is a relatively expensive and complicated process. During the packaging of the active optical device, an optical fiber is precisely aligned therewith and is glued and/or bonded in position. The active optical device is thereafter sold, purchased, or used with the fiber permanently attached thereto. The alignment and attachment of the fiber to the active optical device presents an additional process and cost in the production thereof.
By contrast, the communication industry has devoted much attention to the splicing of two fibers together and, as a result, has developed many suitable types of devices or assemblies for accomplishing such coupling or splicing with good reliability and low cost. For instance, one relative low cost and high reliable assembly is disclosed in U.S. Pat. No. 4,915,472 of Liu, which is hereby incorporated by reference. This assembly is commonly referred to as an L-block rotary splice and receives fiber plugs between a sleeve and an L-shaped alignment block. The optical fibers are positioned to be slightly eccentric relative to the central axis of the plugs so that the fibers may be brought into registration with each other by simply rotating one or both of the plugs to the position of maximum signal transmission. The L-block rotary splice provides a relatively simple assembly for mechanically splicing two fibers together.